Experts say funding child nutrition is the highest profit-yielding strategy any country can take. If children are starving, they get sick more easily, need more costly health care, and earn less than adults who had the right nutrition.

Child malnutrition is a global problem. It exists even in rich countries. It affects a large number of children in Asia, especially in south Asia.

In parts of the world, such as sub-Saharan Africa, it threatens child survival.

"Almost every country in Africa today has an acute rate of malnutrition. The question is how high it goes," he said.

New studies published in the Lancet medical journal show that malnutrition causes 45 percent of all deaths in children under the age of five. Other children suffer stunting, meaning their body and brain fail to develop properly.

The problem starts in the womb, says Dr. Robert Black of Johns Hopkins University, who headed the series.

“Undernourished mothers have fetuses that don’t grow as well, so fetal growth restriction itself is a problem. Babies who are born small for their gestational age have increased mortality and increased stunting and developmental problems later," he said.

The researchers say if countries take some simple measures, they can save the lives of one million children a year.

The proposals include giving pregnant women folic acid and calcium supplements, promoting breast feeding, and giving young children vitamin A and zinc supplements.

Harold Alderman is with the International Food Policy Research Institute in Washington and one of the Lancet series' authors.

“For every dollar invested, you can get between eight and ten dollars of economic returns," he said. "And when I do these studies, I say 'look, nobody knows how to say how valuable is saving a life.'"

Alderman says governments profit when they keep children well fed.

“I’m a little puzzled as to why governments still think of investments in nutrition, as how you compensate the poor, 'but we’ll do our productive investments elsewhere.' These are productive investments. There is no question. The numbers are there," he said.

Alderman says investing in child nutrition will improve a country’s economy because well-fed children do better in school and eventually become a stronger labor force. That statement is supported by other research showing that adults who were malnourished as children earn 20 percent less than those who had proper nutrition.